Search (105 results, page 1 of 6)

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Abstract

We propose an extension of a mediator architecture. This extension is oriented to ontology-driven data integration. In our architecture ontologies are not managed by an extemal component or service, but are integrated in the mediation layer. This approach implies rethinking the mediator design, but at the same time provides advantages from a database perspective. Some of these advantages include the application of optimization and evaluation techniques that use and combine information from all abstraction levels (physical schema, logical schema and semantic information defined by ontology). 1. Introduction Although the Web is probably the richest information repository in human history, users cannot specify what they want from it. Two major problems that arise in current search engines (Heflin, 2001) are: a) polysemy, when the same word is used with different meanings; b) synonymy, when two different words have the same meaning. Polysemy causes irrelevant information retrieval. On the other hand, synonymy produces lost of useful documents. The lack of a capability to understand the context of the words and the relationships among required terms, explains many of the lost and false results produced by search engines. The Semantic Web will bring structure to the meaningful content of Web pages, giving semantic relationships among terms and possibly avoiding the previous problems. Various proposals have appeared for meta-data representation and communication standards, and other services and tools that may eventually merge into the global Semantic Web (Berners-lee, 2001). Hopefully, in the next few years we will see the universal adoption of open standards for representation and sharing of meta-information. In this environment, software agents roaming from page to page can readily carry out sophisticated tasks for users (Berners-Lee, 2001). In this context, ontologies can be seen as metadata that represent semantic of data; providing a knowledge domain standard vocabulary, like DTDs and XML Schema do. If its pages were so structured, the Web could be seen as a heterogeneous collection of autonomous databases. This suggests that techniques developed in the Database area could be useful. Database research mainly deals with efficient storage and retrieval and with powerful query languages.

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Abstract

Today's enterprises employ multiple information systems which are independently developed, locally administered, and are different in logical or physical design. To share information across organisational boundaries requires a global query system capable of providing online intelligent assistance to users. Conventional technologies such as schema based query languages and hard coded schema integration are insufficient. Develops a model assisted global query system using an online repository of enterprise metadata, the metadatabase, for global query formulation and processing with adaptiveness and open systems architecture. Presents a definition model for the metadata as a knowledge system. Analyzes the improvements of the new system in relation to the old. Tests a prototype system in a computer integrated manufacturing setting

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Abstract

The project CARMEN ("Content Analysis, Retrieval and Metadata: Effective Networking") aimed - among other goals - at improving the expansion of searches in bibliographic databases into Internet searches. We pursued a set of different approaches to the treatment of semantic heterogeneity (meta-data extraction, query translation using statistic relations and Cross-concordances). This paper describes the concepts and implementation of these approaches and the evaluation of the impact for the retrieval result.

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Abstract

Purpose - This paper seeks to adopt FRBRoo as an ontological approach to integrate heterogeneous metadata, and transform human-understandable format into machine-understandable format for semantic query. Design/methodology/approach - Two cases of use with museum artefacts and literary works were exploited to illustrate how FRBRoo can be used to re-contextualize the semantics of elements and the semantic relationships embedded in those elements. The shared ontology was then RDFized and examples were explored to examine the feasibility of the proposed approach. Findings - FRBRoo can play a role as inter lingua aligning museum and library metadata to achieve heterogeneous metadata integration and semantic query without changing either of the original approaches to fit the other. Research limitations/implications - Exploration of more diverse use cases is required to further align the different approaches of museums and libraries using FRBRoo and make revisions. Practical implications - Solid evidence is provided for the use of FRBRoo in heterogeneous metadata integration and semantic query. Originality/value - This is the first study to elaborate how FRBRoo can play a role as a shared ontology to integrate the heterogeneous metadata generated by museums and libraries. This paper also shows how the proposed approach is distinct from the Dublin Core format crosswalk in re-contextualizing semantic meanings and their relationships, and further provides four new sub-types for mapping description language.

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Abstract

Discusses the development and implementation of models for indexing and searching information resources on the Internet. Examines briefly the results of a simple query on a number of existing search systems and discusses 2 proposed index metadata structures for indexing and supporting search and discovery: The Dublin Core Elements List and the Semantic Header. Presents an indexing and discovery system based on the Semantic Header

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Abstract

In this talk we present a retrieval model based on social ontologies. More specifically, we utilize the Wikipedia category system in order to perform semantic searches. That is, textual input is used to build queries by means of which documents are retrieved which do not necessarily contain any query term but are semantically related to the input text by virtue of their content. We present a desktop which utilizes this search facility in a web-based environment - the so called eHumanities Desktop.

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Abstract

It has been claimed that topic metadata can be used to improve the accuracy of text searches. Here, we test this claim by examining the contribution of metadata to effective searching within Web sites published by a university with a strong commitment to and substantial investment in metadata. The authors use four sets of queries, a total of 463, extracted from the university's official query logs and from the university's site map. The results are clear: The available metadata is of little value in ranking answers to those queries. A follow-up experiment with the Web sites published in a particular government jurisdiction confirms that this conclusion is not specific to the particular university. Examination of the metadata present at the university reveals that, in addition to implementation deficiencies, there are inherent problems in trying to use subject and description metadata to enhance the searchability of Web sites. Our experiments show that link anchor text, which can be regarded as metadata created by others, is much more effective in identifying best answers to queries than other textual evidence. Furthermore, query-independent evidence such as link counts and uniform resource locator (URL) length, unlike subject and description metadata, can substantially improve baseline performance.

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Abstract

At present cataloguing of Internet resources are on 2 levels. At level 1, the description of resources is contained in local library catalogues, along with bibliographic surrogates for all other materials that the library access, based on AACR2/MARC systems. At level 2, Internet resources are organized independently of any library agency. These include separate catalogues of selected resources, subject browsing lists and robot-generated search tools, and focus exclusively on Internet resources. A 3rd level needs to be developed - a metacatalogue - whereby a user can identify specific library catalogues to include in a search query of other Internet databases

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Abstract

Advice given in printed and web-based sources on HTML META tags with NAME='DESCRIPTION' is surveyed.To determin patterns of relationships among descriptions on the same site,links were followed automatically from 460 pages registered withYahoo! and previously found to contain descriptions.Sites where the registered page pointed to many other pages were significantly less likely to reuse the same description on those other pages; where different descriptions were used words from the registered page's description tended to appear toward the beginnings of other descriptions.

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Source

Open Password. 2019, Nr.666 vom 22.11.2019, [https://www.password-online.de/?wysija-page=1&controller=email&action=view&email_id=823&wysijap=subscriptions&user_id=1045]

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Abstract

The aim of this study is to analyse differences between tags on LibraryThing's web page and tag clouds in their "Library-Thing for Libraries" service, and assess if, and how, the Library-Thing tag moderation and limitations to the size of the tag cloud in the library catalogue affect the description of the information resource. An e-mail survey was conducted with personnel at LibraryThing, and the results were compared against tags for twenty different fiction books, collected from two different library catalogues with disparate tag cloud sizes, and Library-Thing's web page. The data were analysed using a modified version of Golder and Huberman's tag categories (2006). The results show that while LibraryThing claims to only remove the inherently personal tags, several other types of tags are found to have been discarded as well. Occasionally a certain type of tag is in-cluded in one book, and excluded in another. The comparison between the two tag cloud sizes suggests that the larger tag clouds provide a more pronounced picture regarding the contents of the book but at the cost of an increase in the number of tags with synonymous or redundant information.

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Abstract

This paper deals with the problem of modeling Web information resources using expert knowledge and personalized user information for improved Web searching capabilities. We propose a "Web information space" model, which is composed of Web-based information resources (HTML/XML [Hypertext Markup Language/Extensible Markup Language] documents an the Web), expert advice repositories (domain-expert-specified metadata for information resources), and personalized information about users (captured as user profiles that indicate users' preferences about experts as well as users' knowledge about topics). Expert advice, the heart of the Web information space model, is specified using topics and relationships among topics (called metalinks), along the lines of the recently proposed topic maps. Topics and metalinks constitute metadata that describe the contents of the underlying HTML/XML Web resources. The metadata specification process is semiautomated, and it exploits XML DTDs (Document Type Definition) to allow domain-expert guided mapping of DTD elements to topics and metalinks. The expert advice is stored in an object-relational database management system (DBMS). To demonstrate the practicality and usability of the proposed Web information space model, we created a prototype expert advice repository of more than one million topics/metalinks for DBLP (Database and Logic Programming) Bibliography data set. We also present a query interface that provides sophisticated querying fa cilities for DBLP Bibliography resources using the expert advice repository.

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Date

30. 3.2002 19:45:22

Source

Revista Española de Documentaçion Cientifica. 22(1999) no.2, S.198-219

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Date

16. 7.2000 20:58:22

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Source

Library hi tech. 22(2004) no.1

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Abstract

Maintaining a library of digital objects of necessaryy requires maintaining metadata about those objects. The metadata necessary for successful management and use of digital objeets is both more extensive than and different from the metadata used for managing collections of printed works and other physical materials. While a library may record descriptive metadata regarding a book in its collection, the book will not dissolve into a series of unconnected pages if the library fails to record structural metadata regarding the book's organization, nor will scholars be unable to evaluate the book's worth if the library fails to note that the book was produced using a Ryobi offset press. The Same cannot be said for a digital version of the saure book. Without structural metadata, the page image or text files comprising the digital work are of little use, and without technical metadata regarding the digitization process, scholars may be unsure of how accurate a reflection of the original the digital version provides. For internal management purposes, a library must have access to appropriate technical metadata in order to periodically refresh and migrate the data, ensuring the durability of valuable resources.

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Abstract

This site provides a collection of schemas, i.e., html tags, that webmasters can use to markup their pages in ways recognized by major search providers. Search engines including Bing, Google and Yahoo! rely on this markup to improve the display of search results, making it easier for people to find the right web pages. Many sites are generated from structured data, which is often stored in databases. When this data is formatted into HTML, it becomes very difficult to recover the original structured data. Many applications, especially search engines, can benefit greatly from direct access to this structured data. On-page markup enables search engines to understand the information on web pages and provide richer search results in order to make it easier for users to find relevant information on the web. Markup can also enable new tools and applications that make use of the structure. A shared markup vocabulary makes easier for webmasters to decide on a markup schema and get the maximum benefit for their efforts. So, in the spirit of sitemaps.org, Bing, Google and Yahoo! have come together to provide a shared collection of schemas that webmasters can use.

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Abstract

Knowledge management in digital libraries is a universal problem. Keyword-based searching is applied everywhere no matter whether the resources are indexed databases or full-text Web pages. In keyword matching, the valuable content description and indexing of the metadata, such as the subject descriptors and the classification notations, are merely treated as common keywords to be matched with the user query. Without the support of vocabulary control tools, such as classification systems and thesauri, the intelligent labor of content analysis, description and indexing in metadata production are seriously wasted. New retrieval paradigms are needed to exploit the potential of the metadata resources. Could classification and thesauri, which contain the condensed intelligence of generations of librarians, be used in a digital library to organize the networked information, especially metadata, to facilitate their usability and change the digital library into a knowledge management environment? To examine that question, we designed and implemented a new paradigm that incorporates a classification system, a thesaurus and metadata. The classification and the thesaurus are merged into a concept network, and the metadata are distributed into the nodes of the concept network according to their subjects. The abstract concept node instantiated with the related metadata records becomes a knowledge node. A coherent and consistent knowledge network is thus formed. It is not only a framework for resource organization but also a structure for knowledge navigation, retrieval and learning. We have built an experimental system based on the Chinese Classification and Thesaurus, which is the most comprehensive and authoritative in China, and we have incorporated more than 5000 bibliographic records in the computing domain from the Peking University Library. The result is encouraging. In this article, we review the tools, the architecture and the implementation of our experimental system, which is called Vision.

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Abstract

Purpose - The purpose of this paper is to describe a new approach to a well-known problem for digital libraries, how to search across multiple unrelated libraries with a single query. Design/methodology/approach - The approach involves creating new Dewey Decimal Classification terms and numbers from existing Dublin Core records. In total, 263,550 records were harvested from three digital libraries. Weighted key terms were extracted from the title, description and subject fields of each record. Ranked DDC classes were automatically generated from these key terms by considering DDC hierarchies via a series of filtering and aggregation stages. A mean reciprocal ranking evaluation compared a sample of 49 generated classes against DDC classes created by a trained librarian for the same records. Findings - The best results combined weighted key terms from the title, description and subject fields. Performance declines with increased specificity of DDC level. The results compare favorably with similar studies. Research limitations/implications - The metadata harvest required manual intervention and the evaluation was resource intensive. Future research will look at evaluation methodologies that take account of issues of consistency and ecological validity. Practical implications - The method does not require training data and is easily scalable. The pipeline can be customized for individual use cases, for example, recall or precision enhancing. Social implications - The approach can provide centralized access to information from multiple domains currently provided by individual digital libraries. Originality/value - The approach addresses metadata normalization in the context of web resources. The automatic classification approach accounts for matches within hierarchies, aggregating lower level matches to broader parents and thus approximates the practices of a human cataloger.

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Date

28. 3.2002 9:22:34